Marine oil tank



Patented June 25, 1946 UNITED STAT ES PAT ENT FFIC E MARINE OIL TANKEgbert R. Vorenkamp, Berkeley, Calif.

Application November 21, 1944, Serial No. 564,510

\ 2 Claims.

This invention relates to marine oil tanks of a transportable nature. I

It is the principal object of m present invention to provide an improvedmarine storage tank which is capable of being transported from place toplace, and which is highly'useful in receiving oil contaminated waterballast from ships and automatically separate and retain the oil thereinwhile discharging the water.

It is a further object of my present invention to provide a tank of thecharacter referred to for the storage of volatile fuels, which tank isof a construction eliminating the necessity of venting the gases, whichconstruction is such that extreme tank strength is not required to takecare of the expansion and contraction of contained fuel due totemperature variations.

It is a further object of my present invention to provide an improvedtank of the character referred to which may be anchored in such asubmerged position that while ready access to its contents is permitted,it is practically concealed and is a negligible target.

One form which the invention may assume is exemplified in the followingdescription and illustrated by way of example in the accompanyingdrawing, in which:

Fig. 1 is a view partially in side elevation and partially in verticalsection disclosing a tank embodying the preferred form of my invention.

Fig. 2 is a partial plan view thereof with parts broken away to showcertain features of construction.

Referring more particularly to the accompanying drawing, I0 indicates amarine storage tank which is intended, when in use, to be practicallysubmerged. It can, however, when in this condition, either be anchoredor it can be towed from place to place.

The tank I0 comprises a main cylindrical shell II having a verticalaxis. The shell I I is formed with a bottom I2 having a central openingI4 formed therein. An upstanding cylindrical collar I5, which isopen-ended, surrounds the opening I4. I have found in actual practicethat by providing the collar I5 about the opening I4, suction throughthe opening I4 is eliminated by the drag of the external water when thetank is 'being towed through the sea. I have also found that withoutthis collar I5, the suction drag occasioned by towing or movement of thetank through the water will empty the tank of its contents.

The upper end of the tank is fitted with a hinged cover I6 hinged at oneside of th tank as at IT. Suitable latching means may be provided forthis cover, if desired, in any conventional fashion, but as it is not apart of my present invention, it is not illustrated.

Circumscribing the upper end of the cylindrical shell I I is an annularshell I8 relatively fixed to the main shell II. The annular shell IB isin effect a buoyancy tank. The capacity of this buoyancy tank isrelative to the load capacity of the storage shell II. The buoyancy tankI8 is divided by radial swash plates or bulkheads I9 into a plurality ofcompartments. In the present instance I have intended that thecompartments intercommunicate so that one filling fitting 20 can beemployed to inject or remove water from all of the compartments.However, if desired, the bulkheads I9 can be water-tight and a separatefilling fitting 20 can be provided for each compartment.

It is intended, however, that only sufficient water ballast be employedin the tanks I8 to maintain the free-board between the external waterline and the top of the tank a desired dimension. There will still besufficient buoyancy, however, provided by the tank I8 to prevent theentire tank from completely submerging.

As an example, when gasoline or other highly volatile fuel is stored inthe shell II, it may be desired to have approximately a three-footfreeboard. In other circumstances, it may be desired that thatfree-board be reduced to a matter of inches. Manifestly, by regulatingthe volume of ballast water in the buoyancy shell I8 to conform to thegravity of the contents of the shell II, the free-board may be such asdesired.

I wish to point out here that the opening I4 in the bottom of the shellII is always open. Therefore, when storing gasoline or other highlyvolatile fuel in the tank, the tank may be filled to the very top andthe lid closed, leaving no gas space and providing no vent for thegases. The reason that this can be accomplished is that if the fuelexpands in the shell II, it will expand against the water through theopening I4, and if the fuel contracts, the water will rise in theopening I4 and take its place, thus maintaining the fuel to the top ofthe tank at all times and eliminating any gas problem.

Due to this automatic provision for expansion and contraction of thefuel in the shell II, the tank need not be made excessively strong andneed not have sufiicient inherent strength to take care of the expansionof the fuel as it would have to have if the opening I4 was not provided.

Obviously, my present tank is of use in storing gasoline and other fuelin a marine location. It can be towed to a desired position and thenanchored. In that it has a removable cover plate, access can be readilyhad to the contents of the shell for removal. It is also to be pointedout that due to the low free-board, in that the tank is practicallysubmerged, it presents a very poor target.

My tank has various uses in addition to that just set forth and one ofits uses is to take care of the removal of oil contaminated ballastwater from ships in harbor. In such instances, it is highly desirablethat the oil be not pumped from the ballast tanks of the ship into theharbor. By the use of my present tank, the contaminated ballast watermay be pumped directly into the top of my tank. The oil will continue torise to the top of the shell, while the continued inflow into the shellwill cause the water lowering to the bottom of the tank to dischargethrough the opening 14. of oil, it may be towed to a convenient spot forthe discharge of the oil. In so doing, as previously described, the dragwill not cause a suction to remove the oil from the shell ll due to theprovision of the collar l5.

From the foregoing it is obvious that I have provided a very efiicientand highly efiicient marine tank which has the desirable character isticof enabling volatile fuel to be stored without necessitating making thetank of such strength to overcome expansion of the fuel due When thetank becomes full to temperature variations. The tank has the additionalcharacteristic that it can be used for fuel storage in marine locationswithout being conspicuous and without presenting but a very poor target.

While I have shown the preferred form 01 my invention, it is to beunderstood that various changes may be made in its construction by thoseskilled in the art without departing from the spirit of the invention asdefined in the appended claims.

Having thus described my invention, what I claim and desire to secure byLetters Patent is:

l. A marine tank comprising a main shell for containing oil, a bottom insaid main shell, said bottom having an opening formed therein, anupstanding collar fixed at its lower end to the bottom of the shell atthe periphery of said open ing, said collar being open-ended, a buoyancytank relatively fixed to the shell and circumscribing its upper end, anda removable cover plate for the upper end of the shell. 7 2. A marinetank comprising a cylindrical main shell having a bottom, said bottomhaving an opening formed centrally therein, an openended cylindricalcollar fixed at its lower end to the bottom of the shell at theperiphery of its opening and extending upwardly into the shell, anannular buoyancy tank relatively fixed to the shell and eircumscribingits upper end, and a hinged cover for the upper end of the shell.

EGBERT R. VORENKAMP.

